Cam-operated timer with rotary switch means including movable contacts on the cam

ABSTRACT

The program means of a timing mechanism includes cam means and template means and electrical switching means to operate an appliance, the electrical switching means including mechanical switches responsive to the cam means and electrical shorting means responsive to the template means to cooperate with electrical conductive paths. Various drive means, as well as other features, are included.

United States Patent [191 Homan et al.

CAM-OPERATED TIMER WITH ROTARY SWITCH MEANS INCLUDING MOVABLE CONTACTS ON THE CAM Inventors: William N. Homan, Plainfield;

Maurice E. Schuder, Indianapolis; Richard W. Stafford, Clayton, all of Ind.

Assignee: P. R. Mallory & Co. Inc.,

Indianapolis, Ind.

Filed: July 24, 1972 Appl. No.: 274,490

Related US. Application Data Continuation-in-part of Ser. No. 69,257, Sept. 3, 1970, abandoned.

US. Cl. 200/38 B, 200/36, 200/37 A, 200/38 C, 200/153 L, 307/141.4 Int. Cl. l-I0lh 43/10 Field of Search... 307/l4l.4; 200/38 CA, 38 C, 200/38 B, 38 BA, 11 DA, 36, 37 R, 37 A, 38 R, 153 L [4 1 June 25, 1974 [56] References Cited UNITED STATES PATENTS 3,003,097 10/1961 Jennings 307/14L4 X 3,151,257 9/1964 Anderson et al. 200/36 X 3,231,692 1/1966 Plasko 200/36 3,342,957 9/1967 Burragato et al. 200/38 R 3,586,797 6/1971 Gerhardt et al 200/11 DA Primary Examiner-James R. Scott Attorney, Agent, or Firm-Richard H. Childress; Charles W. Hoffman; Robert F. Meyer [57] ABSTRACT The program means of a timing mechanism inc1udes cam means and template means and electrical switching means to operate an appliance, the electrical switching means including mechanical switches responsive to the cam means and electrical shorting means responsive to the template means to cooperate with electrical conductive paths. Various drive means, as well as other features, are included.

17 Claims, 17 Drawing Figures PATENTEDJIIII 2 5 I974 SHEU 1 0F 8 SPEED SPEED REDUCT'ON INTERMITTENT DRIVE REDuCTION D MEANS U2 L MEANS r D I DRIVEN DRIVER H Dh sus- INTERVAL I MEANS l MOVABLE I J TEMPLATE CAM B CONTACTS I I MEANS MEANS I I l I STATIONARY I I MECHANICAL I I CONTACTS SWITCHES l L I E APPL I AN CE SPEED REDUgTl ON ME NS ESCAPEMENT MEANS fi SPEED REDUCTION N\!\'I\l- MEANS I DH 1 I SUB- D INTERVAL MEANS SPEED' REIRAUECATNISON EE ESCAPEMENT' MEANS r SPEED REDUCTION DH L 3 MEANS INVENTORS NTERVAL WILLIAM N. HOMAN MEANS MAURICE E. SCHUDER RICHARD w. STAFFORD ATTORNEY PATENTEUJuu25 1974 3818.888 sum 2 or 8 RS MAN SCHUDER STAFFORD BY INVENTO WILLIAM N. HO MAURICE E. RICHARD w.

ATTORNE PAI'IZNIED 1914 3.8191886 SHEET 3 IF 8 29 52 i8 l4 K." I I I II I 7 7M 38" L 70% Q 34 Ii III 70' J46 I 4 l6 FIG 5 +6 44 26 INVENTORS WILLIAM N. HOMAN MAURICE E. SCHUDER RICHARD W. STAFFORD BYKMWiW ATTO RN EY PATEHTEDJUHZS I974 3.819.886

SIIEEI IIIIB INVENTORS I50 I 0 WILLIAM N. HOMAN I I43 H6 MAURICE E. SCHUDER I42 RICHARD w. STAFFORD F1439 KAI/#414,44

H8 ATTORNEY PATENTEDJUH25 I974 SHEET 5 BF 8 INVENTORS WILLIAM N. HOMAN MAURICE E. SCHUDER RICHARD W. STAFFORD ATTORNEY PATENTED I974- 3.819.886

SHEET 5 BF 8 v I 258 ,224' O o 232 y Y 224, I I I INVENTORS WILLI N. HOMAN MAURICE SCHUDER RICHARD W. STAFFORD BY Maw,

ATTORNEY CAM-OPERATED TIMER WITH ROTARY SWITCH MEANS INCLUDING MOVABLE CONTACTS ON THE CAM This application is a continuation-in-part of application Ser. No. 69,257, filed Sept. 3, 1970 now abandoned.

This invention relates to timing mechanisms, and more particularly, to timing mechanisms which serve to operate an appliance according to a programmed sequence.

Timing mechanisms such as those which are used to control the operation of appliances, such as dryers, dishwahsers, and washing machines, are increasingly becoming more complex and bulky due to the increased variety of operational sequences needed to be programmed by the timing mechanism. Indeed, present day timing mechanisms have advanced to the point where rapid advance means are included in the timing mechanism to advance the timer over those sequences of operation which may not be desired by the appliance operator. Additionally, some appliances have become so complicated that the timing mechanisms additionally include sub-interval means to provide for sequence other than the normal program sequence of the timer. All of this has caused the timing mechanisms to become complicated, difficult to fabricate and expensive.

Another factor adding to the bulkiness of the timer and which makes it more complicated, is the drive mechanism which drives the programming means of the timer. Normally, an intermittent drive mechanism, sometimes referred to as an escapement, is used as a means for coupling an output shaft of a constant speed motor to the programming means on the timer. The purpose of the intermittent drive mechanism is to provide a periodic, snap-action rotational motion to the control cams. Again, as the appliances become more complicated, the intermittent drive mechanisms or escapements used to actuate the programming means becomes more complicated.

Generally speaking, appliances include elements which may require either high or low currents for their operation. One of the many features of the present invention is to utilize a program means which economically takes advantage of the fact that not all the elements of the appliance need to be operated at high current. Thus the present invention utilizes a programming means which includes a means for completing circuits which carry low current and another programming means which completes circuits requiring high currents. This approach has provided a method of keeping the cost, and bulkiness of the timer to a minimum.

Moreover, because of the tendency for the timers to become complicated, it would be highly desirable if the packaging" of the timer provides a device which is readily adaptable to changing requirements. Thus the housing for the timer and the bussing for the electrical circuits, for example, should be made readily adaptable to changing conditions.

It is, therefore, an object of the present invention to provide a timing mechanism in combination with an appliance which is economical, simple and easy to produce. I

Another object of the invention is to provide a timing mechanism having a program means which includes cam means and template means.

A further object of the invention is to provide a timing mechanism having a program means which includes a cam means and template means wherein the template means includes an electrically insulative film overlaying electrically conductive paths with the film having spaced arcuate slots.

Yet another object of the invention is to provide a timing mechanism having a program means which includes cam means wherein the cam means includes at least two cams each having coded indicia on its outer periphery.

Yet still another object of the invention is to provide a timing mechanism wherein its program means includes cam means and template means and wherein the cam means includes a single cam having coded indicia on at least one face thereof.

Another object of the invention is to provide a timing mechanism having a program means which includes cam means and template means and electrical switching means which includes switch means responsive to the cam means and electrical shorting means responsive to the template means and which cooperate with electrically conductive paths.

Still a further object of the invention is to provide a timing mechanism having a program means which includes cam means and template means, constant speed drive means and means coupling the program means to the constant speed drive means.

Still a further object of the invention is to provide a timing mechanism wherein the means coupling the constant speed drive means to the program means includes intermittent drive means of various configurations.

Another object of the invention is to provide a timing mechanism having a constant speed drive means driving a program means wherein the constant speed drive means includes at least two constant speed motor means.

Yet another object of the invention is to provide a timing mechanism having program means, constant speed drive means advancing the program means at a predetermined rate, and a rapid advance drive means advancing the program means at a faster rate.

Yet still another object of the invention is to provide a timing mechanism having a program means and a sub-interval means providing switching sequences other than that of the program means.

Still another object of the invention is to provide a timing mechanism having a sub-interval means with means coupling the sub-interval means to bussing means.

Another object of the invention is to provide a bussing means for conducting electrical current from one electrically conductive member to another.

Yet another object of the invention is to provide a timing mechanism wherein the housing includes a cover means having means to direct the switching means in a single predetermined direction and wherein the cover cooperates with a base member to provide variable orientations.

These and other objects of the invention will become apparent from the following description taken in conjunction with the accompanying drawings in which:

FlGS. 1-3 are block diagrams illustrating the functional and structural relationship of the elements of the timer;

FIG. 4 is an exploded view of one embodiment of the timing mechanism;

FIG. 5 is a side elevation of the timing mechanism of FIG. 4 with portions thereof being removed for clarity;

FIG. 6 is an enlarged section taken along the lines 6-6 of FIG. 2;

FIG. 7 is an isometric view of the electrical terminal block of FIG. 6;

FIG. 8 is an exploded view of another embodiment of the timing mechanism;

FIG. 9 is a section taken along the lines 9-9 of FIG. 8;

FIG. I0 is a view taken along the line 10-10 of FIG. 8;

FIG. 11 is a bottom view of the timer with portions thereof being removed showing another embodiment of the drive means of the timer;

FIG. Ila is an exploded view of a portion of the drive means of FIG. 11;

FIG. 12 is a view similar to FIG. 11 showing another embodiment of the drive means;

FIG. 13 is an exploded view of a clutch means used in the drive means of the timer;

FIG. 14 is a top view of another embodiment of the timer with portions thereof being removed for purposes of clarity;

FIG. 15 is an enlarged view taken along the line 15-15 of FIG. 14; and

FIG. 16 is a view taken along the line 16-16 of FIG. 15.

Generally speaking, the objects of the invention are accomplished by providing in a timing mechanism a constant speed drive means, program means, and means coupling the program means to the constant speed drive means, and wherein the program means includes cam means and template means and wherein electrical switching means which are responsive to the program means includes switch means responsive to the cam means and electrical shorting means cooperating with electrical conductive paths are responsive to the template means. The timer uses constant speed drive means which may include two synchronous motors, one of the motors being termed a timer motor, the other a rapid advance motor, with means coupling the program means to the constant speed drive means. In those cases where there are two synchronous motors employed, clutch means are utilized to permit the synchronous motors to alternately drive the program means. The means coupling the synchronous motors to the program means includes intermittent drive means of various configurations.

Referring now to FIGS. 1-3, there is presented block diagrams showing the functional and structural relationship between the principle elements of the timer. Referring to FIG. I, it is seen that the timer is basically divided into two sections, a drive means A and a control means B, the drive means being connected to and driving the control means. The control means is divided into two basic sections, a program means P and an electrical switching means E responsive to the program means. Drive means A includes constant speed motors M, (timer motor) and M (rapid advance motor) each having its cooperating speed reduction means and intermittent drive means. The intermittent drive means includes a driver portion and a driven portion. There are two unidirectional clutch means U, and U each having a driver portion D, and a driven portion D,,. As shown, unidirectional drive means U is included as an element of its cooperating speed reduction means. Rapid advance motor M and its cooperating speed reduction means and unidirectional clutch means serves as the rapid advance means for the timer. As shown, the speed reduction means for timer motor M, is coupled to the driver portion of the intermittent drive means. Driver portion D, of unidirectional clutch means U, is coupled to the driven portion of the intermittent drive means while the driven portion D of unidirectional drive means U is coupled to the driven portion D, of unidirectional drive means U,.

With reference to the control means B, program means P includes cam means and template means. The cam means is connected to the driven portion D of unidirectional drive means U,. Electrical switching means E includes mechanical switches responsive to the cam means, and movable and stationary contacts which cooperate with the template means. Rotation of the cam means causes the mechanical switches to open and close. The movable contacts are coupled to the driven portion D, of unidirectional clutch means U, and, as indicated by the arrow, are responsive to the template means and cooperate with the stationary contacts through the template means to provide the switching means. That is, the movable contact will engage the stationary contacts at pre-determined time intervals as determined by the template. As shown, both the mechanical switches and the stationary contacts are electrically coupled to elements of the appliance to be driven. That is, the closing of the mechanical switches and the engagement of the movable contacts with the stationary contacts to close the same completes electrical circuits to elements of the appliance, as indicated, and in a manner well known in the art. Electrical power is supplied to such circuits through the appliance being plugged in" to a suitable electrical outlet. Thus, both the cam means and the template means directly control elements of the appliance. The template means could be used to control low current elements of the appliance, while the cam means with its switches, the high current elements.

The timer also includes a sub-interval means connected between the driver portion of the intermittent drive and the mechanical switches to open and close the switches at intervals other than that provided by the previously noted cam means.

FIG. 2 shows another embodiment of the timer having a different arrangement of the drive section for the timer. Drive means A, in this embodiment, includes constant speed motors M, and M unidirectional clutch means U, and U each having driver and driven portions D, and D,,, speed reduction means associated with the motors, and what comprises the essential difference in the drive means of this embodiment, an escapement means. The escapement means is essentially an intermittent drive means having an input from the motor M, and an output which includes energy storage means which intermittently stores and releases energy to provide the intermittent drive. The output of the escapement means is coupled to the driver portion D, of unidirectional clutch means U,. As in the case of the drive means of FIG. 1, a sub-interval means, is provided. In this embodiment, the sub-interval means is connected between the speed reduction means and the mechanical switches of FIG. 1. The embodiment shown in FIG. 3 is substantially the same as that shown in FIG. 2, the only difference being that unidirectional drive means U is included as part of the escapement means. This arrangement will provide a more compact structure; however, the configuration of FIG. 2 provides for an independently operable and serviceable clutch means.

Referring now to FIG. 4, there is shown an embodiment of the present invention. The timing mechanism 20 is substantially enclosed in a housing means 14 which includes a base member 16 and a substantially square cover 18. Base member 16 includes notches 16 adapted to mate corresponding tongues 18 of the cover 18. Base member 16 provides as a single structural element a means for orienting cover 18 (to be described), a base for the constant speed drive, and for receiving the program means of the timing mechanism. Cover 18 includes removable windows 22 such that access can be gained to switch means 24. Shaft means 26 extends through the housing and is rotatably journalled in base member 16 and cover 18. Shaft means 26 is also axially displaceable, the amount of axial displacement being limited by detent means 28. Detent means 28 includes a spring 29 which is guided and retained by guide means 25 and 27 and grooves 23 m2] which receive spring 29. When shaft means 26 is axially indexed, spring 29 limits the axial displacement of the shaft means through the combination of the spring 29 and grooves 21 and 23.

The essential elements of the timing mechanism 20 include program means 10, electrical switching means 12, constant speed drive means 30 and means 32 coupling the constant speed drive means to the program means so as to be above to drive or operate the program means when the constant speed drive means is energized. Program means includes a template means 34 and a cam means 36. In the present embodiment, cam means 36 includes a single cam 38 having coded indica on at least one face thereof, the coded indicia comprising arcuate cam tracks 38'. Cam 38 is carried by shaft means 26 through hub 40. Hub 40 includes tongues 42 adapted to mate notches 44 of gear means 46. As will be hereinafter described, gear means 46 is coupled to coupling means 32 thus coupling the constant speed drive means to the program means to drive or operate the program means when the constant speed drive means is energized. Also included in hub 40 is a slot 48 adapted to receive pin 50 carried by shaft means 26. The couplingof the cam 38 to the shaft means 26 through the pin and slot arrangement allows the cam to be manually rotated when shaft means 26 is axially displaced to disengage the pin from the slot. The axial displacement of shaft means 26 to manually rotate cam 38 also causes displacement of line switch actuator means 52 which is pivotally mounted on cover 18 through post 53. Displacement of line switch actuator means 52 actuates line switch 56 to cut off electrical power to the timer. This prevents damage to the various switches of the timer when the operator manually rotates cam means 36. Thus cam 38 may be either power driven by constant speed drive means 30 or may be manually operated through the shaft means 26. It is noted that cam means 38 also includes gear teeth 38". Teeth 38" are provided to serve as a coupling means to the coupling means 32 for coupling the constant speed drive means 30 to the program means 10 in case gear means 46 is not used.

Template means 34 includes an electrically insulative film and more particularly a sheet 54 having arcuate slots 56 provided therein. A suitable material for the sheet 54 would be a plastic such as a melamine, for example. Sheet 54 is suitably bonded to a substantially flat board 58 of a dielectric material and electrically conductive paths 60 which are carried by the board. Suitable materials for the electrically conductive paths 60 would be copper, for example, and for the dielectric material an asbestos filled phenolic. Electrically coupled to the conductive paths 60 are electrical terminal means 62. Electrical terminals 62 include extensions 60' of electrically conductive paths 60 separated by extension 58 of board 58. The center ring 64 of the electrically conductive paths serve as an electrical ground. It should be understood that sheet 54 and the conductive paths 60 could be carried on both sides of the board 58.

Electrical switching means 12 includes switch means 24 which are open and closed in response to rotation of cam 38 through cam follower means 66, and electrical shorting means 68 (movable contacts, HO. 1) which cooperates with template means 34 to selectively engage electrically conductive paths 60 (stationary contacts, FIG. 1) through arcuate slots 56. Electrical shorting means 68 includes a plurality of wipers 70 comprising fingers carried by cam 38 through base 77, the wipers being resiliently retained by fingered aperture 71 snapping over bosses 73. In the event there are electrically conductive paths and template means 34 carried on both sides of board 58, wipers 70 are also carried by gear 46. Rotation of gears 38 or 46 causes rotation of wipers 70 or 70 to wipe over sheet 50 of template means 34 and portions of electrically conductive paths 60 through arcuate slots 56 of the sheet.

'Constant speed drive means 30 includes at least one timer motor 11, which may be of the synchronous type. As occasion demands, however, a second motor 13 may be used as a drive means for rapid advancement of the program means of the timer.

Referring now to FIGS. 4 and 6, it is seen that switch means 24 includes a plurality of fixed electrical contacts 72 and 72' and a plurality of movable contacts 74 and 74' each carried by a plurality of switch blades 76, 76' and 78respectively. The fixed contacts are separated by spacer means 73. Unitarily constructed with switch blade 78 is previously mentioned cam follower means 66. Rotation of cam 38 biases cam follower means 66 through cam tracks 38' such that movable contacts 74 and 74' selectively engage or close with fixed contacts 72 and 72. Unitarily constructed with each of the switch blades are electrical terminals 80. There is also a row of dummy electrical terminals 80' which may be utilized with the electrical terminals 80 to provide additional outlets. Although not shown, electrical terminals 80 as well as electrical terminals 62 may be plugged into" a suitable wiring harness (not shown) which includes electrical wiring electrically connecting various elements of an appliance to a suitable electrical power source and/or each other in a manner well known in the art.

A" of the electrical terminals may be electrically connected together in various configurations through electrical bussing means 82. As shown, the electrical bussing means and a substantial portion of the electrical terminals are all contained within a compartmentalized bussing block housing 84 so as to be substantially electrically isolated from each other. Bussing block housing 84 and terminal block 117 are easily removable such that the switches and terminals are readily replaceable. With reference to FIG. 7, the electrical terminals are additionally isolated from each other through a series of compartments 86 formed by intersecting walls 88 and 88' extending from bussing block housing 84 to provide the separate compartments.

It is noted that the switch means 24 with the electrical terminals 80 extend from a single side of the cover 18 to point in a predetermined direction. This aids in making the timer neat and compact. The orientation or direction of the switch means and electrical terminals may, however, be readily changed merely by reorienting the cover, all three of the previously described tongues 18 and grooves 16 being of the same shape and size.

Referring now to FIGS. 8 and 9, there is shown another emobidment of the invention. Timing mechanism is essentially the same as that of FIG. 4, the principle difference being in the cam means 90 of the program means of the timer. In this embodiment, cam means 90 includes a cam stack 92 comprising individual earns 94 having coded indicia in the form of arcuate steps 96 on their outer periphery. As shown, the top cam carries electrical shorting means 98 which as in the embodiment of FIG. 4, includes wipers in the fomi of a plurality of fingers 97 which wipe template means 100 and electrically conductive paths 102. More specifically, as in the embodiment of FIG. 4, template means 100 comprises a thin film or sheet 101 having arcuate slots 103 provided therein through which fingers 97 engage conductive paths 102 as the fingers are rotated over the sheet 101. Switching means 194, responsive to the rotation of the cam means 90, is similar to that of the embodiment of FIG. 4 and includes cam followers 106 unitarily constructed with switch blades 108 which carries a plurality of movable contacts 110 adapted to engage a plurality of fixed contacts 112 which are separated by spacer means 114 when cam followers 106 are biased in accordance with rotation of cam means 90 through the coded indicia 96. The switching means and their associated electrical tenninals are carried by terminal block 115 which is easily removable so that the switches and the tenninals can be replaced as a unit.

There is a gear means 116 unitarily constructed with cam means 90 which is similar to gear means 46 and which is coupled to an element of the coupling means 32 (FIG. 9) coupling the constant speed drive means 30 to the cam means 90. Shaft means 118 is rotatably journaled in bushing I20 and hub 125 of the cam means 90 is also axially displaceable. The amount of axial displacement is limited by detent means 122 which includes a spring 124 adapted to engage either one of grooves 121 and 132. There is a floating cam ring 126 rotationally coupled to a collar 128 through an annular groove 130 formed in the collar and flange 132. Collar 128 is coupled to shaft means 118 through knurl 134. Axial displacement of the shaft means 118 causes teeth 136 of the collar 128 to engage corresponding teeth 138 of cam means 90. Cam means 90 also includes an axial indexing cam lobe 140 adapted to engage an actuator means 142 which includes a bell crank 143 pivotally carried by channel 144 and adapted to engage floating cam ring 126 at rim 146. As

shown in FIG. 9, the timer has just completed its operating cycle and cam lobe 140 has engaged bell crank 143 to lift floating cam ring 126. Upon the lifting of floating cam ring 126, cam surface 126' disengages line switch actuator 148 thus releasing spring loaded movable line switch 150 to open the power circuits to the timer. Also, when floating cam ring 126 was raised, shaft means 118 was indexed inwardly, teeth 136 engaged teeth 138 of cam means such that cam means 90 can now be manually operated or rotated by the operator with the line switch being open. For the next power cycle, shaft means 118 is indexed inwardly such that the cam surface 126 engages line switch actuator to close the line switch 150.

The operation of the two embodiment can now be discussed with reference to the elements of the timer so far described. With the shaft means of the timer being indexed for power operation, one of the constant speed motors 11 will rotate the cam means of the program means of the timer as well as theelectrical shorting means carried by either the cam means or the gear means used to couple the constant speed drive means to the program means. Rotation of the cam means selectively opens and closes the mechanical switches through the cam tracks or steps as well as causing rotation of the fingers of the electrical shorting means so as to cooperate with the electrically conductive paths in accordance with the arcuate slots provided in thin sheets of the template means. Engagement of the tingers with the conductive paths completes an electrical circuit through the terminals and to electrical circuits of the appliance to which the terminals are electrically connected. In like manner, electrical circuits are completed through the appliance when the mechanical switches are closed through the cam tracks or steps. As will be hereinafter described, the other motor of the constant speed drive means can be used as a rapid advance means to quickly rotate both the cam means and the electrical shorting means to a desired starting point of the appliance program cycle.

It .should be understood that while the invention has been described in relation to a stationary template means with rotating shorting means, that the invention need not be so limited and that their functional rela' tionship could be reversed.

The drive means A, A, and A" of FIGS. l-3 can now be described. It is understood that such drive means includes the constant speed drive means 30 and the means 32 coupling the constant speed drive means with the program means. Referring to FIG. 10, the drive means A of FIG. 1 is shown. Since FIG. 10 is a view taken along the line l0l0 of FIG. 8, the complete speed reduction means and motors 11 and 13 (FIGS. 4 or 8) are not shown. It is to be understood that such speed reduction means would include gears and pinions normally termed gear trains associated with motors. Each of the speed reduction means includes an output pinion 152 and 154 which mesh with idler gears 156 and 158. Idler gear 158 meshes with gear means 46, 116. Rapid advance motor 13 and its associated speed reduction means including output pinion 154 serve as a rapid advance means of the present embodiment. In accordance with the illustration of FIG. 1, the speed reduction means for the rapid advance would also include a unidirectional clutch means. While not shown in this embodiment, such unidirectional clutch is the same as clutch means 208 and 268 shown and described with respect to the embodiments of FIGS. 11 and 12 respectively, the clutches being directly operable off the motor output pinion. As will be apparent in the description with respect to FIGS. 11 and 12, the clutch means permits operation of timer motor 11 independent of the rapid advance motor 13. Pinion 154 meshes with gear 46, 116 to impart power driven constant speed rotation to the gear and thus the cam means and the electrical shorting means connected to the gear.

Intermittent drive means 160 includes cylindrical drive means 162 and gear means 164. Cylindrical drive means 162 has, as shown, a generally cylindrical peripheral surface 166 with a recess 168 formed therein. The cylindrical drive means also includes actuator means 170 which includes posts 172 and 172' disposed at each side of the recess 168. Cylindrical drive means 162 is coupled to idler gear 156 through gear or pinion 174. Gear means 164 includes a gear 176 having two sets of teeth 176' and 176", one set of which (teeth 176') has a greater thickness than the other. Unidirectional clutch means 178 includes pawl 180 pivotally carried on gear 176 through posts 182, and ratchet wheel 184 which is constructed unitarily with gear 158. Pawl 180 is resilient with its free end sprung about post 186. Gear 158 with the ratchet wheel 184 and gear 176 are independently rotatably carried on shaft 188. As will become apparent,-unidirectional clutch means 178 permits manual operation of the timer and also permits the rapid advance motor to be operable independent of the timer motor.

In operation, motor output pinion 152 is driven at a constant speed in a predetermined direction by timer motor 11 and its associated gear train. Pinion 152 will drive the cylindrical drive means through gear 156 and gear 174. With timer motor 11 energized, rapid advance is de-energized with the timer motor being independently. Assuming cylindrical drive means 162 can be rotated in a counterclockwise direction, as the actuator means 170 approaches the case of gear 176, posts 172' will engage one of the teeth 176 of less'than full thickness, while one of the teeth 176 of greater thickness engages recess 168 as it is driven by post 172. When recess 168 passes the interference paths of gear 176, the full teeth 176 engages the side 166 of the cylindrical drive means 162 thus preventing further rotation of the gear 176. Thus, the intermittent drive means will only advance when the actuator means 170 of the cylindrical drive means comes into engagement with the gear 178. The intermittent rotation of the gear 176 causes rotation of ratchet wheel 184 through the engagement of tooth 180' with the ratchet wheel. Rotation of ratchet wheel 184 causes rotation of gear 158 which in turn causes rotation of gear 46, 116.

The use of the directional clutch means 187 in combination with the holding feature of the cylindrical drive means 162 permits the program means of the timer to be manually set without driving through" the constant speed drive motor. Specifically, because of the holding feature of the cylindrical drive means, the tooth 180' of pawl 180 will disengage from ratchet wheel 184 when the program means is manually rotated in the proper direction.

Unidirectional clutch means 178 also permits the rapid advance motor to operate independent of the timer motor. Specifically, when gear 158 is rotated to rotate gear 46, 116, ratchet wheel 184 will be rotated counterclockwise to overrun tooth of pawl 180.

As an optional feature, drive means A also includes sub-interval means 190. Sub-interval means 190 includes at leastone lever 192 and cam means 194. Cam means 194 is unitarily constructed with cylindrical drive means 162 and includes at least one track 196 of coded indicia. There may be two of such tracks and likewise another lever in which case the two tracks would be separated by a peripheral ridge 198. As the cam follower 192' of each lever rides over the coded indicia, the lever pivots to actuate sub-interval electrical switches (not shown). As in the case of the previously described mechanical switches, the closing of the sub-interval switches completes electrical circuits to an appliance to which electrical terminals of the switches have been connected. The use of the sub-interval means allows for shorter time sequences than are normally available from the program means of the timer.

Referring now to FIG. 11, there is shown another embodiment of the drive means A embodying the concepts of F l0. 2. Generally speaking, drive means A includes a first speed reduction means or gear train 200 coupled to motor output pinion 202 of timer motor 11 (F I68. 4 or 8), escapement means 204, a second speed reduction means or gear train 206 coupled to motor output pinion 211 of rapid advance motor 13 (FIGS. 4 or 8) through clutch means 208, and dampening means 210. The output pinion 212 of the escapement means 204 is coupled to gear means 46, 116 through another gear 214. Speed reduction means 206 with clutch means 208 and its associated constant speed motor 13 provide the rapid advance means for the present embodiment. Clutch means 208 includes a ratchet means 216 which cooperates with a pawl means (not shown) but which is located on the opposite face of the gear 209 carrying the ratchet means. When rapid advance is called for, motor pinion 211 drives gear 209 with the pawl overriding the ratchet means 216 to allow pinion 218 to rotate which subsequently rotates gear 220 which in turn meshes with gear 222 which is unitarily constructed with output pinion 212. Conversely, when the timer motor is operating, the pawl will engage the ratchet means 216 to prevent rotation of gear 209 such that the rapid advance motor will not be driven.

Escapement means 204 includes cam drive means 224, pulse cam means 226, energy storage means 228, and stop means 230. Drive cam means 224 is unitarily constructed with gear 232, while pulse cam means 226 is unitarily constructed with gear 234. Drive cam means 224 includes a gradually rising contour ending in a sharp step 224'; likewise, pulse cam means 226 has a gradually rising contour ending in a step 226. Energy storage means 228 includes a coil spring 236 sandwiched between the drive cam means 224 and the pulse cam means 226 with each end of the spring being connected to posts 224 and 226" respectively. Stop means 230 includes a pair of pawls 238 and 240 pivotally mounted on posts 238 and 240. The pawls are mounted about 180 apart thus allowing the pulse cam to be advanced 180 as will be hereinafter described. The pawls are spring biased through leaf springs 238" and 240" which are biased against the speed reduction housing 113.

There is a clutch means 213 disposed between gear 222 and the base of housing 113. The clutch means,

which is shown in FIG. lla, permits manual rotation of the cam means and electrical shorting means of the timer and further permits the timer motor to operate independently of the rapid advance motor. As shown in FIG. 11a, clutch means 213 includes spring biased actuator member 274 which is coupled to gear 222 through posts 278 and 280 engaging slots 274' and 274" actuator member 274 being spring biased through coil spring 282. Actuator member 274 has a clutch face 284 in the form of a camming surface which is adapted to mate clutch face 286. As shown this whole assembly is rotatably carried on post 285. When gear 222 is rapidly rotated through the rapid advance motor and its gear train, clutch face 284 will override clutch face 286 that there is no driving of the escapement means or the timer motor and its gear train. Likewise if manual rotation of the cam means and the electrical shorting means is desired, clutch face 284 will override clutch face 286.

In the operation of the escapement, the constant speed motor drives motor output pinion 202 in a predetermined direction. The constant rotational drive from the motor will then be transmitted through the speed reduction means 200 to gear 232. It should be here noted that when the escapement means is assembled and the coil spring 236 is sandwiched between the two cams, the coil spring is pre-loaded such that its ends are disposed approximately adjacent each other as shown in FIG. 11. This pre-loads the escapement means. Rotation of gear 232 will cause rotation of drive cam means 224 which in turn will bias stop pawl 238 outward. Continued rotation of drive cam means 224 will bias pawl 240 outward and allow pawl 238 to be deflected inwardly. As pawl 240 is biased outwardly, step 226 will become disengaged from the pawl 238, the energy in coil spring 236 will be released, and pulse cam 226 will be permitted to advance 180 until it engages pawl 240. The 180 advancement of pulse cam 226 will cause l80 advancement of gear 234. The advancement of gear 234 will cause the advancement of gear 242 with which is meshes and the advancement of gear 242 will cause a like advancement of output pinion 212. As previously noted, clutch means 209 prevents the escapement output from driving the rapid advance motor.

In order to retard the snap-action characteristics generated by the escapement means, there is provided a dampening means 210. This is a desirable feature in the present arrangement since, if the snap-action characteristics were not somewhat slowed down, there would be an excessive wear on parts. Dampening means 210 includes a slider 244 which slides on the housing of the timer through tangs 246 and 246' and which is guided by posts 248 and 248' which cooperate with apertures 250 and 250', and ratchet wheel 252. Ratchet wheel 252 is unitarily constructed with gear 242 by staking tabs 242' of gear 242 in apertures 252' of the ratchet wheel. As shown, the slider 244 includes an elongated centrally disposed aperture 254, and follower cam 256 and 256 which are adapted to intermittently engage ratchet wheel 252. Thus as gear 242 iy intermittently advanced I80", teeth 256 and 256' will alternatelyengage and disengage from the ratchet wheel 252 as slider 244 slides back andforth.

As gear 232 is being driven at a constant speed, an output gear 258, which is unitarily constructed with gear 232, will also be driven at a continuous output.

There is thus provided an output means for an optional sub-interval means 260 if desired. Sub-interval means 260 includes a gear 262 meshes with gear 258 and a sub-interval cam 264. By providing a suitable follower means for the sub-interval cam, sub-interval switching can readily be accomplished.

Referring now to FIG. 12, there is shown the drive mans A" illustrated in FIG. 3. A rapid advance means in this embodiment includes a motor 13 (FIGS. 4 or 8) and motor output pinion 266 which meshes with unidirectional clutch means 268, idler gear 270 which is carried by shaft 272 which also carries gear 274 and which is disposed outside the timer speed reduction housing. Gear 274 meshes with gear 277 (FIG. 13) and gear 277 meshes with gear 46,116. Unidirectional clutch means 268 is similar to that of unidirectional means 208 illustrated in FIG. 11 and therefore when rapid advance is called for, the output from the rapid advance motor will not drive the timer motor 11. A second speed reduction means 276 is coupled to timer motor 11 (FIGS. 4 or 8) through a motor output pinion 278 and includes a number of gears and pinions to achieve the desired speed reduction. The escapement means 280 of the present embodiment includes rotary positioning means 282, reciprocating regulating means 284, and intermittent rotary output means 286. Rotary positioning means 282 includes a cam 288 having coded indicia thereon adapted to bias reciprocating means 284 in a manner hereinafter to be described. Cam 288 is carried or otherwise coupled to gear 290 of speed reduction means 276.

Reciprocating regulating means 284 includes a slider 292. Slider 292 includes a rim 294 having a centrally disposed aperture 296 therein, a pair of elongated apertures 298 and 298 and stop means 300. Stop means 300 includes steps 302 and 320' of rim 294. Apertures 298 and 298 receive posts 304 and 304' such that the slider can be guided or piloted as it slides or reciprocates.

Intermittent rotary output means 286 includes a stop means 306 and pinion 308. Stop means 306 includes an arcuate step 310' of cam 310 adapted to engage either one of the stop means 300 of slider 292. Intermittent rotated output means 286 is biased through energy storage means 312. Energy storage means 312 includes a coil spring 314 sandwiched between cam 288 and stop means 306. The coil spring is coupled to posts 310" and 288'. Stop means 306 is carried by or otherwise coupled to ratchet wheel 316. Although it is not necessary in the practice of the invention, pinion 308, ratchet wheel 316 and stop means 306 are formed as a single integral piece.

In operation, when the escapement means is first assembled, coil spring 314 is disposed such that one end of the coil spring is about from the position shown in FIG. 12. That is, the two ends of the coils will be approximately adjacent each other. Speed reduction means 276 is driven at a constant rate of speed in a predetermined direction. Rotation of gear 290 will cause rotation of rotating positioning means 282. The coded indicia of cam 288 acting against the slope 318 of stop means 306 will cause reciprocating regulating means 284 to slide back and forth. Assuming that step 310' is in engagement with step 302', as reciprocating regulating means 284 slides forward, the step will become disengaged thus allowing the energy in coil spring 314 to be released to rotate stop means 306 clockwise for approximately 180 until the step 310' engages step 302 of the slider. Rotation of stop means 306 causes rotation of output pinion 308. Thus as the reciprocating regulating means 284 slides back and forth, the process will be repeated with the slides back and forth, the process will be repeated with the step 310' leaving step 302 and rotating approximately 180 until it becomes engaged again with step 302'. Thus, it is seen that an intermittent motion of approximately 180 is important to the output pinion 308. Output pinion 308 meshes with gear 276 of unidirectional clutch means 320 (FIG. 13).

As was true in the embodiment of FIG. 11, there is a tendency for the rotating output means 286 to snap from one step to the other at a very fast rate of speed and with a considerable force. Such action could cause damage to the apparatus. Therefore, there is provided a dampening means 322 which tends to retard the quick, snap-action of the intermittent rotating output means 286, without any substantial loss of energy build-up in the spring. Dampening means 322 includes ratchet wheel 316 and pivotally mounted pawl means 324 adapted to engage the ratchet wheel. Engagement of the ratchet wheel 316, while not completely stopping the rotational movement of the intermittent rotating output means 286, will retard its motion. The dampening means 324 also, because of the shape of the ratchet teeth and the pawls, serve as a no-back means for the escapement.

With reference to FIG. 13, unidirectional clutch means 320- is substantially similar to clutch means 178 shown and described in the embodiment of FIG. 10. It includes a ratchet wheel 326 carried by gear 277, a pawl 328 carried on gear 330 through posts 332. Pawl 328 is resilient with its free end sprung" about posts 334. Output pinion 308 meshes with gear 330. The intermittent rotation of output pinion 308 causes rotation of ratchet wheel 326 through the engagement of tooth 328' with the ratchet wheel. Rotation of ratchet wheel 326 causes rotation of gear 276 which in turn causes intermittent rotation of gear 46, 116. Operation of the rapid advance means independent of the timer motor as well as manual operation is provided with the clutch means 320 in a manner similar to clutch means 178 of the embodiment of FIG. 10.

Returning to FIG. 12, drive means A" also includes a sub-interval means 336. Sub-interval means includes, in this embodiment, a cam 338 coupled to or otherwise carried by one of the gears 340 of speed reducing means 276, and a cam follower means (not shown). As the cam follower rides over the coded indicia of the cam 338, it selectively actuates sub-interval electrical switches (not shown). The use of the sub-interval allows for shorter time sequences than are available from the normal program means of the timer.

Referring now to FIGS. 14-16, there is shown another embodiment of a sub-interval means and a bussing means for the timing mechanism. Sub-interval means 336 includes a cam means 338, and switch means 340. Cam means 338 which is responsive to constant speed drive means 30 through pinion 335 and gear 337 includes a cam 334 having two peripheral edges 346 (one not shown) of coded indicia separated by a ridge 348. Switch means 340 includes two movable contact blades 350 (one not shown) each having an electrical contact 352 adapted to engage contacts 342 of stationary blades 343 (one not shown). A cam LII follower 351 is connected to or otherwise carried by movable blade 350. Both the movable contact blades and the stationary contact blades are spring loaded and trapped in posts 354, 356, 358, 360, 362 and 364. A sheet of insulting material 366 electrically isolates the blades from the housing (not shown) of the timing mechanism. A similar sheet separates the individual blades. Electrical leads 370 and 371 electrically connect the switching means to electrical terminals 372 and 373. Electrical terminals 372 and 373 are trapped in slots (FIG. 4) 374 by way of nodes 376 lanced from the terminals. As shown, the whole sub-interval means with the electrical leads are disposed within the housing of the timing mechanism. Thus, there is no external switching or lead wires normally found in timing mechanisms using subinterval means. It is noted that all of the electrical tenninals are oriented from the direction shown in FIG. 4. This illustrates the previously described orientation ability of the housing means of the timing mechanism.

Referring particularly to FIGS. 15 and 16, there is illustrated the bussing means of this embodiment. Bussing means 380 includes a thin metal strip 382 having fingers 384 extending from the sides thereof. The strip 382 engages one wall of the compartment 386 of terminal block 388 while an end 390 engages a cavity 392 extending from the end of the compartment with the central portion 394 of the finger engaging either the contact blades 396 or the electrical terminals 398. This arrangement assures a good electrical connection between the terminals and the contact blades when selectively electrically connecting the various terminals and switch blades together. Any number and variations of such connections can be made, with either the switch means responsive to the cam program means being electrically connected together including connections between same levels of current, and connections between high and low current levels.

What is claimed is:

l. A timing mechanism comprising:

A. a housing means;

B. at least one motor carried by said housing means;

C. at least one timing cam rotatable within said housing means;

D. a gear train coupling said timing cam to said motor so as to be rotated by said motor;

E. switches carried on said housing opening and closing in response to rotation of said timing cam;

F. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths; and

G. a plurality of fingers carried by said timing cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths.

2. A timing mechanism according to claim 1, wherein there is a single timing cam having arcuate cam tracks on at least one side thereof.

3. A timing mechanism according to claim 1 wherein there are a plurality of timing cams each having arcuate steps on their periphery.

4. A timing mechanism according to claim 1, wherein said sheet of material is melamine.

5. A timing mechanism according to claim 1 wherein said dielectric material is an asbestos filled phenolic, and said electrically conductive paths are copper.

6. A timing mechanism according to claim 1, wherein there are two of said motors and wherein said means coupling said cam to said motor includes clutch means permitting rotation of said cam by one of said motors independent of the other.

7. A timing mechanism according to claim 1, wherein said means coupling said timing cam to said motor comprises an intermittent drive means converting a constant speed output from said motor to an intermittent rotational movement to said timing cam.

8. A timing mechanism comprising:

A. a housing means;

B. at least one motor carried by said housing means;

C. at least one timing cam rotatable within said housing means;

D. switches carried on said housing opening and closing in response to rotation of said timing cam;

E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposingportions of said electrically conductive paths;

F. a plurality of fingers carried by said cam to be ro tatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths;

G. a gear train coupled to said motor for rotation;

and

H. an intermittent drive means comprising:

a. a first cam coupled to a gear of said gear train so as to be rotated by said motor,

b. a sliding member reciprocating in response to rotation of said cam, and stop means carried by said sliding member,

c. a second cam having at least one arcuate step adapted to engage said stop means, a coil spring connecting said second cam to said first cam, and

d. an output means connecting said second cam to said timing cam.

9. A timing mechanism according to claim 8 wherein said intermittent drive means further comprises a dampening means co-acting with said second cam to retard the snap-acting characteristics of said intermittent motion transmission means.

10. A timing mechanism according to claim 9 wherein said dampening means comprises a ratchet wheel connected to said second cam and a pivotally mounted pawl engaging said ratchet wheel.

11. A timing mechanism according to claim 8 wherein aid timing mechanism further comprises a third cam connected to said motor providing a subinterval timing period, and a switch opening and closing in response thereto.

12. A timing mechanism comprising:

A. a housing means;

B. at least one motor carried by said housing means;

C. at least one timing cam rotatable within said housing means;

D. switches carried on said housing opening and closing in response to rotation of said timing cam;

E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths;

F. a plurality of fingers carried by said cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths;

G. a gear train coupled to said motor for rotation;

and

H. an intermittent drive means comprising:

a. a cylindrical rotating member connected to a gear of said gear train to be rotated thereby,

b. a recess provided in a periphery of said cylindrical member, I

c. posts extending from a surface of said cylindrical member on each side of said recess,

d. a gear engaging said cylindrical rotating member, said gear having two sets of teeth, one of said sets having a greater thickness than the other,

e. rotation of said cylindrical rotating member causing engagement of said posts with said sets of teeth so as to rotate said gear as the set of teeth of greater thickness rotates through said recess, further rotation of said cylindrical member engaging a set of teeth of greater thickness with the .periphery of said cylindrical drive means so as to hold said gear from rotation, and

f. an output means connecting said cylindrical drive member to said timing cam.

13. A timing mechanism according to claim 12 further comprising a second timing cam connected to said cylindrical rotating member and having at least one track of coded indicia on its periphery and at least one pivotally mounted lever engaging said track.

14. A timing cam according to claim 13 wherein there are two of said tracks separated by a peripheral ridge, and two of said levers engaging same.

15. A timing mechanism comprising:

A. a housing means;

B. at least one motor carried by said housing means;

C. at least one timing cam rotatable within said housing means;

D. switches carried on said housing opening and closing in response to rotation of said timing cam;

E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths;

F. a plurality of fingers carried by said cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths;

l7 18 G. a gear train coupled to said motor for rotation; tation at predetermined positions, and

and e. an output means connecting said second cam to H. an intermittent drive means comprising: said timing cam.

a. a pair of oppositely disposed pivotly mounted 16. A timing mechanism according to claim 15 pawls, wherein said output means includes at least one gear b. spaced first and second cams rotatably mounted and said intermittent drive means further comprises on a shaft between said oppositely disposed dampening means co-acting with said gear to retard pawls, snap-acting characteristics of said intermittent drive c. a coil spring disposed between and connecting means said first and second cams together, 17. A timing mechanism according to claim 16 d. said first cam connected to a gear of said gear wherein said dampening means comprises:

train and biasing said pivotally mounted pawls as a. a ratchet wheel carried by said gear, and

it rotates said second cam having an arcuate step b. a sliding member having cam follower intermitselectively engaging one of said pawls in accortently engaging said ratchet wheel.

dance with its biased position so as to stop its ro- 5 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 819, 886 l Dated 06/25/74 Inventor(s) William N. Homan, Maurice E. Schuder & Richard W.

. l Stafford It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 7 line 54, insert --and-- after "90" C01. 8 line 14, delete "140 and substitute therefore ---l48--.

Col. 11 line 62, delete iy" and substitute therefore ---is---.

Col. 13 line 5 & 6 delete 'slides back and forth, the process will be repeated with the" Col. 13 line 62, delete "334" substitute therefore 344--.

Col. 15 line 61, delete "aid and substitute therefore -said Signed and sealed this 11th day of February 1975.

(SEAL) Attest:

. C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks ORM (10-69) V uscoMM-oc scan-Poo u.s. sovzmmsm ram-nus enact: a 93 o UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 819, 886 Dated 06/25/74 Inventor(s) William N. Homan, Maurice E. Schuder & Richard W.

' Stafford It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 7 line 54, insert -andafter "90" C01. 8 line 14, delete "140 and substitute therefore -l48---. I

Col. 11 line 62, delete "iy" and substitute therefore ---is---.

Col. 13 line 5 & 6 delete "slides back and forth, the process will be repeated with the" Col. 13 line 62, delete "334" substitute therefore --344-.

Col. 15 line 61, delete "aid" and substitute therefore --said-'- Signed and sealed this 11th day of February 1975.

(SEAL) Attest I C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Attesting Officer and Trademarks I (10-59) USCOMM-DC scan-poo u.s. sovcmmnn "mums o l' lcz 869 93 o 

1. A timing mechanism comprising: A. a housing means; B. at least one motor carried by said housing means; C. at least one timing cam rotatable within said housing means; D. a gear train coupling said timing cam to said motor so as to be rotated by said motor; E. switches carried on said housing opening and closing in response to rotation of said timing cam; F. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths; and G. a plurality of fingers carried by said timing cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths.
 2. A timing mechanism according to claim 1, wherein there is a single timing cam having arcuate cam tracks on at least one side thereof.
 3. A timing mechanism according to claim 1 wherein there are a plurality of timing cams each having arcuate steps on their periphery.
 4. A timing mechanism according to claim 1, wherein said sheet of material is melamine.
 5. A timing mechanism according to claim 1 wherein said dielectric material is an asbestos filled phenolic, and said electrically conductive paths are copper.
 6. A timing mechanism according to claim 1, wherein there are two of said motors and wherein said means coupling said cam to said motor includes clutch means permitting rotation of said cam by one of said motors independent of the other.
 7. A timing mechanism according to claim 1, wherein said means coupling said timing cam to said motor comprises an intermittent drive means converting a constant speed output from said motor to an intermittent rotational movement to said timing cam.
 8. A timing mechanism comprising: A. a housing means; B. at least one motor carried by said housing means; C. at least one timing cam rotatable within said housing means; D. switches carried on said housing opening and closing in response to rotation of said timing cam; E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths; F. a plurality of fingers carried by said cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths; G. a gear train coupled to said motor for rotation; and H. an intermittent drive means comprising: a. a first cam coupled to a gear of said gear train so as to be rotated by said motor, b. a sliding member reciprocating in response to rotation of said cam, and stop means carried by said sliding member, c. a second cam having at least one arcuate step adapted to engage said stop means, a coil spring connecting said second cam to said first cam, and d. an output means connecting said second cam to said timing cam.
 9. A timing mechanism according to claim 8 wherein said intermittent drive means further comprises a dampening means co-acting with said second cam to retard the snap-acting characteristics of said intermittent motion transmission means.
 10. A timing mechanism according to claim 9 wherein said dampening means comprises a ratchet wheel connected to said second cam and a pivotally mounted pawl engaging said ratchet wheel.
 11. A timing mechanism according to claim 8 wherein aid timing mechanism further comprises a third cam connected to said motor providing a sub-interval timing period, and a switch opening and closing in response thereto.
 12. A timing mechanism comprising: A. a housing means; B. at least one motor carried by said housing means; C. at least one timing cam rotatable within said housing means; D. switches carried on said housing opening and closing in response to rotation of said timing cam; E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths; F. a plurality of fingers carried by said cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths; G. a gear train coupled to said motor for rotation; and H. an intermittent drive means comprising: a. a cylindrical rotating member connected to a gear of said gear train to be rotated thereby, b. a recess provided in a periphery of said cylindrical member, c. posts extending from a surface of said cylindrical member on each side of said recess, d. a gear engaging said cylindrical rotating member, said gear having two sets of teeth, one of said sets having a greater thickness than the other, e. rotation of said cylindrical rotating member causing engagement of said posts with said sets of teeth so as to rotate said gear as the set of teeth of greater thickness rotates through said recess, further rotation of said cylindrical member engaging a set of teeth of greater thickness with the periphery of said cylindrical drive means so as to hold said gear from rotation, and f. an output means connecting said cylindrical drive member to said timing cam.
 13. A timing mechanism according to claim 12 further comprising a second timing cam connected to said cylindrical rotating member and having at least one track of coded indicia on its periphery and at least one pivotally mounted lever engaging said track.
 14. A timing cam according to claim 13 wherein there are two of said tracks separated by a peripheral ridge, and two of said levers engaging same.
 15. A timing mechanism comprising: A. a housing means; B. at least one motor carried by said housing means; C. at least one timing cam rotatable within said housing means; D. switches carried on said housing opening and closing in response to rotation of said timing cam; E. a substantially flat dielectric material carried by said housing in spaced relation to said cam, electrically conductive paths carried on at least one side of said dielectric material, a sheet of electrically insulative material bonded to said dielectric material and said electrically conductive paths, and slots provided in said sheet exposing portions of said electrically conductive paths; F. a plurality of fingers carried by said cam to be rotatable therewith and engaging said sheet and said exposed portions of said electrically conductive paths; G. a gear train coupled to said motor for rotation; and H. an intermittent drive means comprising: a. a pair of oppositely disposed pivotly mounted pawls, b. spaced first and second cams rotatably mounted on a shaft between said oppositely disposed pawls, c. a coil spring disposed between and connecting said first and second cams together, d. said first cam connected to a gear of said gear train and biasing said pivotally mounted pawls as it rotates said second cam having an arcuate step selectively engaging one of said pawls in accordance with its biased position so as to stop its rotation at predetermined positions, and e. an output means connecting said second cam to said timing cam.
 16. A timing mechanism according to claim 15 wherein said output means includes at least one gear and said intermittent drive means further comprises dampeninG means co-acting with said gear to retard snap-acting characteristics of said intermittent drive means.
 17. A timing mechanism according to claim 16 wherein said dampening means comprises: a. a ratchet wheel carried by said gear, and b. a sliding member having cam follower intermittently engaging said ratchet wheel. 